Fire Science and Engineering (한국화재소방학회논문지)

Korean Institute of Fire Science and Engineering (한국화재소방학회)
권호 표지
DOI QR코드

DOI QR Code

Characteristics of Elastic Wave in Fire damaged High Strength Concrete using Impact-echo Method

충격반향기법을 이용한 화해를 입은 고강도 콘크리트의 탄성파 특성

  • Lee, Jun Cheol (School of Architecture and Civil Engineering, Kyungpook National Univ.) ;
  • Lee, Chang Joon (Dept. of Architectural Engineering, Chungbuk National Univ.) ;
  • Kim, Wha Jung (School of Architecture and Civil Engineering, Kyungpook National Univ.) ;
  • Lee, Ji Hee (School of Architecture and Civil Engineering, Kyungpook National Univ.)
  • 이준철 (경북대학교 건축토목공학부) ;
  • 이창준 (충북대학교 건축공학과) ;
  • 김화중 (경북대학교 건축토목공학부) ;
  • 이지희 (경북대학교 건축토목공학부)
  • Received : 2014.08.13
  • Accepted : 2015.02.04
  • Published : 2015.02.28
Download PDF
⟨ Previous Next ⟩

Abstract

In this study, the damages of high strength concrete exposed to high temperature have been evaluated by the impact echo method. Elastic wave velocity and dynamic modulus of elasticity were measured by the impact echo method, and the compressive strength and the static modulus of elasticity were measured by the compression testing method after exposure to high temperature. The results showed that elastic wave velocity has a linear correlation with the compressive strength and dynamic modulus of elasticity has a linear correlation with static modulus of elasticity. Based on results, it is concluded that the impact echo method can be effectively applied to evaluate the mechanical properties of fire damaged high strength concrete.

본 연구에서는 충격반향기법을 이용하여 화해를 입은 고강도 콘크리트의 화재손상정도를 평가하였다. 100 MPa급의 고강도 콘크리트 시편을 제조하여 $100{\sim}800^{\circ}C$의 고온에 2시간 동안 노출한 후 충격반향기법의 응답스펙트럼을 이용하여 시편의 탄성파 속도를 측정하였으며, 이를 이용하여 동탄성계수를 산출하였다. 이후 직접 압축강도 실험을 통해 시편의 잔존압축강도와 정탄성계수를 측정하였다. 실험결과, 노출되는 온도가 높을수록 탄성파의 속도, 동탄성계수, 잔존압축강도, 정탄성계수가 저하되는 경향을 나타냈으며, 탄성파 속도와 압축강도, 동탄성계수와 정탄성계수는 선형적인 상관관계를 나타냈다. 따라서 충격반향기법을 이용하여 화해를 입은 고강도 콘크리트의 화재손상정도를 평가하는 것이 가능하다고 판단된다.

Keywords

References

  1. R. Felicetti, "The Drilling Resistance Test for the Assessment of Fire Damaged Concrete", Cement and Concrete Composite, Vol. 28, No. 4, pp. 321-329 (2006). https://doi.org/10.1016/j.cemconcomp.2006.02.009
  2. M. Sansalone and N. J. Carino, "Detecting Delaminations in Concrete Slabs with and without Overlays Using the Impact-echo Method", ACI Materials Journal, Vol. 86, No. 2, pp. 175-184 (1989).
  3. M. Sansalone, J. M. Lin and W. B. Street, "Determining the Depth of Surface-opening Cracks Using Impact-generated Stress Waves and Time-of-flight Techniques", ACI Materials Journal, Vol. 9, No. 2, pp. 168-177 (1998).
  4. Y. Lin and M. Sansalone, "Detecting Flaws in Concrete Beams and Columns Using the Impact-echo Method", ACI Materials Journal, Vol. 89, No. 4, pp. 394-405 (1992).
  5. W. F. Tawhed and S. L. Gassman, "Damage Assessment of Concrete Bridge Decks Using Impact-echo Method", ACI Materials Journal, Vol. 99, No. 3, pp. 273-281 (2002).
  6. K. Kesner, M. Sansalone and P. W. Poston, "Detection and Quantification of Distributed Damage in Concrete Using Transient Stress Waves", ACI Materials Journal, Vol. 101, No. 4, pp. 318-326 (2004).
  7. A. Ghorbanpoor and N. Benish, "Non-destructive Testing of Wisconsin Highway Bridge", Wisconsin Highway Research Program Final Report, Wisconsin Department of Transportation (2003).
  8. G. Epasto, E. Proverbio and V. Venturi, "Evaluation of Fired-damaged Concrete Using Impact Echo Method", Materials and Structures, Vol. 43, pp. 232-245 (2010).
  9. S. W. Shin, S. Y. Kim and J. S. Kim, "Applicability of Impact-echo Method for Assessment of Residual Strength of Fire-damaged Concrete", Journal of the Korea Institute for Structural Maintenance and Inspection, Vol. 17, No. 5, pp. 105-112 (2013). https://doi.org/10.11112/jksmi.2013.17.5.105
  10. IAEA, "Guidebook on Non-destructive Testing of Concrete Structures" (2002).
  11. KS F 2405, "Method of Test for Compressive Strength of Concrete" (2010).
  12. JSCE, "JSCE-SF5: Method of Test for Compressive Strength and Compressive Toughness of Steel Fibre-Reinforced Concrete", Concrete Library of JSCE (1984).
  13. C. S. Poon, Z. H. Shui and L. Lam, "Compressive behavior of Fiber Reinforced High Performance Concrete Subjected to Elevated Temperature", Cement and Concrete Research, Vol. 34, No. 12, pp. 2215-2222 (2004). https://doi.org/10.1016/j.cemconres.2004.02.011
  14. C. S Poon, S. Azhar and Y. L. Wong, "Performance of Metakaolin Concrete at High Temperatures", Cement and Concrete Composite, Vol. 25, No. 1, pp. 83-89 (2003). https://doi.org/10.1016/S0958-9465(01)00061-0
  15. B. Wu, X. P. Su and J. Yuan, "Effect of High Temperature on Residual Mechanical Properties of Confined and Unconfined High Strength Concrete", ACI Materials Journal, Vol. 99, No. 4, pp. 399-479 (2004).